Even before Yom Kippur, the people with more time, resources and organization had their sukkot at least partially built - I could see them going up in driveways or balconies or glimpse them in backyards. All the bookstores had signs about esrogs (citrons) and the sukkah stores (analogous to Christmas tree stores, I guess) were opening for their one month of business, and the sukkah builders (teen-age boys, mostly) had their flyers out - there is no mitzvah to *build* a sukkah, just to "dwell" in one. All the signs of the holiday.
But after Yom Kippur, things escalate. Last Sunday, you could hear hammers and drills (and, I suspect, heavy duty staple guns) all over Flatbush, as people used their one day off to get their mini-construction done. Other people dragged out fiberglass panels to clip together, and we got out the framework and nylon tent walls that make up our sukkah. (In fact, since I had an errand, Jonathan put the framework up himself. It's really well engineered.)
I should ask what one of our neighbors thinks - he's Italian Catholic, but everyone around him is Orthodox, so there's at least one Sukkah in every backyard and the occasional front yard. It must seem odd.
Last night, I happend to be on Avenue J, one of the big shopping streets in Midwood. And - how do I describe this? In Park Slope and other neighborhoods in NYC, most of the bodegas and fruit stands start selling Christmas trees in December or so. They line the street side of the sidewalk with the trees, leaving a passageway between the stores and the trees. It's crowded and smells lovely and it's a sign of the season.
In Midwood, there are tables manned by yeshiva boys selling the Four Species (citron, palm branch, willows and myrtles) in the same approximate position. And it's crowded and smells lovely. There are also tables and shops selling decorations because one of the joys of the season is to decorate the sukkah (the best being the crafts made by kids in school and camp, of course. We make do with Mylar.) People use lights, too, but for some reason, those are at their cheapest in January. ;)
Jonathan just called - he's bought our own lulav and etrog for the holiday. We also need to buy a worklight because ours broke and we do need to light our sukkah.
And in two weeks, it will all be gone, except for the stray sukkot whose owners haven't been able to take down in time (you need a two or three stretch of dry days, really, to make sure it's not wet.)